from django.shortcuts import render
from django.http import HttpResponseRedirect,Http404
from django.core.urlresolvers import reverse
from django.contrib.auth.decorators import login_required

from learning_logs.models import Topic,Entry
from learning_logs.forms import TopicForm,EntryForm

# Create your views here.
def index(request):
    '''学习笔记主页'''
    return render(request,'learning_logs/index.html')


@login_required
def topics(request):
    '''显示所有的主题'''
    topics = Topic.objects.filter(owner=request.user).order_by('date_added')
    context = {'topics':topics}
    return render(request,'learning_logs/topics.html',context)


@login_required
def topic(request,topic_id):
    '''显示单个主题以及其所有的条目'''
    topic = Topic.objects.get(id=topic_id)
    if topic.owner != request.user:
        raise Http404
    entries = topic.entry_set.order_by('-date_added')
    context = {'topic':topic,'entries':entries}
    return render(request,'learning_logs/topic.html',context)


@login_required
def new_topic(request):
    '''添加新主题'''
    if request.method != 'POST':
        # 未提交数据：创建一个新表单
        form = TopicForm()
    else:
        # POST 提交的数据，对数据进行处理
        form = TopicForm(request.POST)
        if form.is_valid():
            new_topic = form.save(commit=False)
            new_topic.owner = request.user
            new_topic.save()
            return HttpResponseRedirect(reverse('learning_logs:topics'))
    context = {'form': form}
    return render(request, 'learning_logs/new_topic.html', context)


@login_required
def new_entry(request,topic_id):
    '''在制定的主题中添加一个新的条目'''
    topic = Topic.objects.get(id=topic_id)
    if topic.owner != request.user:
        raise Http404

    if request.method != 'POST':
        # 未提交数据：创建一个新表单
        form = EntryForm()
    else:
        # POST 提交的数据，对数据进行处理
        form = EntryForm(data=request.POST)
        if form.is_valid():
            new_entry = form.save(commit=False)
            new_entry.topic = topic
            new_entry.save()
            return HttpResponseRedirect(reverse('learning_logs:topic', args=topic_id))
    context = {'topic': topic, 'form': form}
    return render(request, 'learning_logs/new_entry.html', context)


@login_required
def edit_entry(request,entry_id):
    entry = Entry.objects.get(id=entry_id)
    topic = entry.topic

    if topic.owner != request.user:
        raise Http404

    if request.method != 'POST':
        # 未提交数据：创建一个新表单
        form = EntryForm(instance=entry)
    else:
        # POST 提交的数据，对数据进行处理
        form = EntryForm(instance=entry,data=request.POST)
        if form.is_valid():
            form.save()
            return HttpResponseRedirect(reverse('learning_logs:topic', args=str(entry.topic_id)))
    context = {'entry': entry,'form':form}
    return render(request,'learning_logs/edit_entry.html', context)
